1. Field of the Invention
The present invention relates to a chair footrest ring positioning structure characterized in that a guide region tilts downward and is concavely disposed on the outer surface of any one side of the lower segment of the tightening case, and on which anti-slip pads are fixed therein and grooves are concavely disposed peripherally thereon. Thus, bumps extending from the inner side of the sleeve corresponding in shape to the middle of the footrest ring and fitted around the tightening case are inserted into the grooves of the tightening case, and the middle pipe of the chair is rotated to move the tightening case by a predetermined distance and thereby causing the guide region to undergo a displacement to drive the insertion of the bumps, to effectuate dynamic adjustment and thus achieve a predetermined degree of tightness.
2. Description of the Prior Art
A conventional footrest ring coupled to a tall chair and positioned at a predetermined height is characterized in that a tightening component of appropriate tightness is disposed at a predetermined segment of a middle pipe of the chair. Thus, the tightening component allows a sleeve to be held in the middle of the footrest ring, and the middle of the footrest ring is of a predetermined width. Hence, the footrest ring is confined to the predetermined segment of the middle pipe and thus is convenient to place a foot on.
Although the footrest ring in operation is tightened, it is predisposed to tightness inadequacy after long use.
In view of the aforesaid drawback of the prior art, the present invention provides a chair footrest ring positioning structure characterized in that a guide region tilts downward and is concavely disposed on the outer surface of any one side of the lower segment of the tightening case, and on which anti-slip pads are fixed therein and grooves are concavely disposed peripherally thereon. Thus, bumps extending from the inner side of the sleeve corresponding in shape to the middle of the footrest ring and fitted around the tightening case are inserted into the grooves of the tightening case, and the middle pipe of the chair is rotated to move the tightening case by a predetermined distance and thereby causing the guide region to undergo a displacement to drive the insertion of the bumps, to effectuate dynamic adjustment and thus achieve a predetermined degree of tightness.